function validate_form(){
        var e = document.getElementById('smsfrom');
        var eAlert = "Please provide a valid mobile phone number.\nStarting 07.";
        var em;
         if (!e.value) {
                 alert (eAlert);
                 return false;
         }
         em = e.value.replace(/[^0-9]/g, '');
         if ((!em) || (em.length != 11)) {
                 alert (eAlert);
                 return false;
         }
 return true;
   }